Making the transition: Toshiba outlines its transition to lead-free manufacturing for its line of semiconductor products.

As part of a commitment to respond to customer requirements for lead-free electronic components, Toshiba Corp., the parent company of Toshiba America Electronic Components Inc. (TAEC), is implementing new manufacturing procedures to support the current industry movement to lead-free manufacturing.

This document presents information on the industry initiative to transition to lead-free products, along with technical information on Toshiba's lead-free products, transition schedule and other related information.

LEAD-FREE DEFINED. As discussed in more detail below, various regulations will limit the use of lead(Pb) in products. As a result, the terms "Lead(Pb)-Free" or "Pb-Free" have become commonly used by the electronics industry to designate products that are intended to satisfy the various regulations regarding lead. However, at present, there is no legally established uniform standard for the level of lead that will be allowed into a product under the various regulations. Notwithstanding the lack of a uniform legal standard, the electronics industry has generally adopted a standard to 0.1 percent by weight.

Under these circumstances, Toshiba will define Lead(Pb)-Free in accordance with the industry standard as containing less than 0.1 percent lead by weight. This does not mean that Toshiba products that are labeled Lead(Pb)-Free are entirely free of lead. During a transitional phase, in addition to Lead(Pb)-Free products, TAEC will also offer products that have Lead(Pb)-Free terminals, which will be referred to as "Lead(Pb)-Free Finish." The Lead(Pb)-Free Finish products may contain greater than 0.1 percent lead by weight in portions of the product other than the terminals.

INDUSTRY INITIATIVE. One of the current environmental initiatives facing semiconductor and electronics manufacturers is to comply with a variety of regulations and proposed regulations from various jurisdictions around the world. These initiatives will regulate or restrict the use of lead or impose additional requirements when lead is used in products. For example, the European Community directives for Waste Electrical and Electronic Equipment (WEEE) and Restriction of Hazardous Substances (RoHS) state in Directive 2002/95/EC that the use of lead and certain other substances must be regulated by July 1, 2006. (For more information on WEEE and RoHS, see "Europe Calling," p. 58, in the Feb. 2004 issue of Recycling Today.)

In the United States, at least 29 states have proposed or adopted legislation that will regulate or restrict the use of lead or impose additional requirements for products that contain lead. Some of these regulations are linked to the European Community's RoHS/WEEE Directive 2002/95/EC. For example, California's SB20 (See "Law and Disorder," p. 126, in the April issue of Recycling Today.) will prohibit an electronic device from being sold or offered for sale in California if the electronic device is prohibited from being sold in the European Union on or after the date of its manufacture in light of the presence of heavy metals. The bill will take effect Jan. 1, 2006, or the date that the EU Directive 2002/95/EC takes effect, whichever is later. In addition, California's SB20 also incorporates provisions of the Electronic Waste Recycling Act of 2003, which establishes provisions and fees for disposing of electronic devices.

These regulations limiting the use of lead in semiconductors and electronics equipment will have widespread impact on the global marketplace, requiring Lead(Pb)-Free assemblies by mid-2006 for products sold in Europe. Within this time frame, global suppliers must convert to Lead(Pb)-Free alternatives completely or maintain dual production processes with duplicate sets of parts, with and without lead, which will have to be carefully tracked.

Almost all electrical and electronic products incorporate semiconductor devices soldered into printed circuit boards. For some time, tin-lead solder--which combines tin and lead has--been widely used for electrical connections because of its electrical and mechanical characteristics. Today, based on the Lead(Pb)-Free initiative, the industry is seeking alternative solders and soldering processes.

TOSHIBA'S PLANS. As a technology company, TAEC is making solutions available to enable customers to comply with pending Lead(Pb)-Free legislation by implementing new manufacturing procedures and using new materials. Toshiba has given increased attention to finding Lead(Pb)-Free solutions for its products and has transitioned a portion of its manufacturing to Lead(Pb)-Free in 2003.

TAEC is committed to working with its customers to be able to offer products that meet customers' specific Lead(Pb)-Free criteria. The company is also taking an active role in regulatory standards in an effort to meet manufacturability and reliability under any new guidelines. Representatives from TAEC and Toshiba have participated in each of the annual IPC/ JEDEC (the Association Connecting Electronics Industries and the Solid State Technology Association, respectively) conferences on Lead(Pb)-Free manufacturing.

TAEC is also scrutinizing the business issues associated with such a manufacturing transition. These issues include customer service, supply chain and inventory management, materials management, supply continuity and industry coordination.

TAEC is striving for a smooth transition by making sure the testing, qualification and re-qualification of parts meets its customers' needs. It is also carefully evaluating the entire supply chain in order to effectively manage all aspects required for supply continuity. Some of TAEC's customers are not considering the move to Lead(PB)-Free components presently, so this will involve management of duplicate parts as the market dictates. In cases where both Lead(Pb)-Free and non-Lead(Pb)-Free components are available, new parts numbers will be issued to enable identification of the Lead(Pb)-Free variant.

The Lead(Pb)-Free measures the company is pursuing vary from product to product. However, the first step in TAEC's transition plan is making the terminals for certain semiconductor products Lead(Pb)-Free. Toshiba has carefully evaluated soldering in terms of materials, chemicals, terminal finishes and thermal resistance to choose the optimal alternative to be applied in each product category. More detailed Lead(Pb)-Free plans for specific product categories are available online at www.semicon.toshiba.co.jp/eng/prd/ memory/doc/pdf/bde0051b.pdf.

SOLDER PRECAUTIONS. Generally, the soldering temperature of Lead(Pb)-Free solder is higher than that of conventional tin-lead solder, so it is essential to ensure that the soldering temperature is not in excess of the head-resistance temperature of the components.

The conversion to Lead(Pb)-Free manufacturing cannot be accomplished overnight. Surface-mount (SMT) assembly lines, especially in the United States, may need to have dual lines using Lead(Pb)-Free products and traditional products that are not Lead(Pb)-Free.

The Lead(Pb)-Free manufacturing process may allow for Lead(Pb)-Free products to be processed on a traditional line (i.e., backwards compatibility) and for traditional products to be processed on a Lead(Pb)-Free line (i.e., forward compatibility).

The maximum heat-resistance-assured temperature of reflow soldering is increased from the present 240 degrees Celsius to 260 degrees Celsius for Lead(Pb)-Free soldering. As a result, Lead(Pb)-Free manufacturing requires careful planning and inventory control to ensure that Lead(Pb)-Free parts are not intermixed with products that are not Lead(Pb)-Free.

CUSTOMER QUALIFICATION. Toshiba is working closely with customers to match its roadmap for transitioning to Lead(Pb)-Free to their Lead(Pb)-Free implementation plans. Some customers are already moving aggressively to Lead(Pb)-Free manufacturing. For customer qualification, some customers have submitted their requirements in writing or have sent surveys regarding Toshiba's Lead(Pb)-Free implementation plans. Toshiba encourages customers to meet to discuss their specific requirements and will provide samples for customer qualification and testing upon request.

This white paper was prepared by Toshiba America Electronic Components Inc. Quality Assurance Department and the Lead(Pb)-Free Implementation Team. More information is available online at www.toshiba.com/ taec.